Clinch-on nut



ox iginal Filed Nov. 7, 1935 2 Sheets-Sheet l fizderir/tl/lws May 16,1939.

F. N. ROSS CLINCH-ON NUT Original Filed Nov. 7, 1935 2 Sheets-Shem 2Patented May 18, 1 939 4 m anion-0am to Ash aesrpsratlsns'fllehigsn' a mseen: No. more, No-

vslsbsr'hmi. Serialile.

The present application for United StatesLettersPatentofwhichthisspeciflcationisapart constitutes acontinuationof my application for ticularly with simple and fabricationof blanks having opposite-faces, preferably flat blanks such as standardnuts, to produce clinchteristics on nuts having novel charac Heretoforethere have been threegeneral type of clinch-on nuts used in theindustry, one-being the D-type clinch-on nut made as a screw machineproduct; the second being the cage type of clinch-on nut wherein astandard nut is enclosed in'a'sheet metal cage. which cage performs aclinchingoperation; andathirdtypewhereina bar of special shape is cutoffand fabricated so as to produce ear members which perform the clinch-onoperation, one assembly being that shown in the Mitchell United StatesLetters Patent No. 1.852.978.

'Anyclinch-on nutmaybestated tobean attachment article of manufacture,including a flangeoraheadwithaseatfaceandaahankextending from the seatface, the shank being adapted -for insertion into an aperture of thesheet material usually sheet metal in which the nut is applied, and theseatface of the flange being adapted for abutting against one face ofthe sheet material, and the extremity of the shank extending beyond theother face of the sheet materialbeingadaptedtobeclinchedoveragainst theother face of the sheet material in opposition to the flange.

1 'It is very desirable in the use of clinch-on nutsto'preventturningoftheshankintheapertures in which they are inserted,and for this P 1 1088 the shanks are preferably multi-cornered and areinserted into multi-cornered apertures.

" The production of an attachment article with thecage,inthataportlonofthewallofthenut itselfls so fabricated as to provide aclinch-on structure; thisproducesaclinch-on nut-whichis (a ss-ss) type.It further provides a nut-which makes it very easy to flnd a thread,which provides a seat all the way around the clinch-on portion to givegreater strength, and which when assembled is a thin, neat-appearingnut.

. A further object of the invention is to provide an attachment articlehaving a multi-cornered shank adapted to be formed by machining a blankentirely by rotary cutting operations, so as to enable the attainment ofminimum production costs.

A further object of the invention has to do with a method carried out bya machine for continuously fabricating the improved clinch-on nuts fromblanks having opposite faces, preferably flat blanks such as standardnuts, said machine being so arranged and constructed as to fabricate andform the clinch-on part of the nut in two operations and to form theclinch-on portion in a D or c shape in another operation.

The foregoing and other objects are attained by the attachment articlesof manufacture, parts, combinations, and sub-combinations, and methodsof making the same, which comprise the present invention, and the natureof which is set forth in the following general statement, and preferredembodiments of which articles and of a machine for carrying out themethod are set forth by way of example in the following description, andwhich are particularly and distinctly pointed out and set forth in theappended claims forming part hereof.

The nature of the improved attachment article may be stated in generalterms as including preferably in a one piece metal article made from ablank having opposite faces preferably by rotary cutting machiningoperations performed entirely upon one face of the blank, a flangehaving a transverse seat face, and a shank extending from tachmentarticle may be described as including a,

body having two opposite transverse end faces, side faces bounding theend. faces, and curved or 'tion with 1 cage-type nuts, but whicheliminates arcuate rabbets between one of the end faces and the sidefaces, each rabbet having a transverse seat face located between the endfaces and a curved preferably cylindric arcuate face at an 3; cagsorscrew machine anglewiththsseatfaceandtheoneendfase.

Other features of the invention have to do with details of the clinch-onnut itself and with details of the method and the construction andarrangement of the fabricating machine, as is more clearly set forth inthe specification and claims.

In the drawings; by way of example Figurre 1 is an elevation view,largely diagrammatic, of a machine for continuously feeding blankshaving [opposite faces, preferably flat blanks as shown in the form ofstandard nuts, fabricating the same to form clinch-on nuts and 20delivering them as a completed article;

Fig. 2 is a face elevation of a clamping device which is adapted toreceive the blanks'having opposite faces, preferably flat blanks asshown in the form of standard nuts and feed the same to 2B the variousfabricating stations;

Fig. 3 is a plan view of the structure shown in Fig. 2.

Fig. 4 is a longitudinal sectional view of a standard nut blank or unit,and having opposite 80 faces;

Fig. 4a is a longitudinal sectional view of a blank having oppositefaces in the form of a fiat unit, which may be preferably provided witha bore as shown in Fig. 4b, and then threaded to form the nut blank orunit of Fig. 4, which may be a preferred blank or unit for fabricatingby the machine of Figs. 1, 2, and 3, by which the improved method iscarried out, although. the blanks or units of either Fig. 4a or Fig. 41)may be fabricated 40 by the machine, and subsequently bored or piercedand threaded, or threaded;

V Fig. 4b is a longitudinal sectional view of the blank or unit of Fig.4a after being provided with a bore by boring or piercing; 45 Fig. 5 isa sectional view similar to Fig. 4 illushating the first step offabrication of the blank orunit of Fig, 4 to form a novel clinch-on nut;

Fig. 6 is a view similar to Figure 5 except showing the secondfabrication step of the blank or '50 unit of Fig. 4 whereby theclinch-on wall or shank is finally formed;

Fig. '7 is an enlarged detached fragmentary elevation illustrating thestep of fabricating the clinch-on parts or shanks of the improvedclinchn nuts to have a plurality of curved faces and corners, andgenerally D or C shapes; and

Fig. 8 is a sectional view taken on line 88, of Fig. 7..

Similar numerals refer to similar parts throughout the drawings.

The production of standard nuts such as shown at 2, Fig. 4, has become ahighly specialized industry; machines for upsetting and threading blanksto form the standard nuts are so highly specialized that these standardnuts can be purchased on the open market at an extremely low price. Asmany hundreds of clinch-on nuts are used on very automobile, it will beseen that the 7 question of cost is a very important one. This is one ofthe reasons why I prefer in many cases to start with a standard nut,because the same can be purchased already threaded, at an extremely lowprice. A standard nut is however a 75 blank having opposite faces madefrom fiat ma- 2,1sa,esa

terial which may be either sheet or strip material, usually metal, andmost frequently steel.

Instead of placing the blank having opposite faces, as shown herein astandard nut, in an automatic screw machine or the like, and fabricatingor cutting the same by tools fed towards the sides as well as the endsor opposite faces, I preferably fabricate the blank, as shown a nut,only by rotary cutting tools fed along their axes of rotation into oneend or face of the blanks, the first operation being shown in Fig. 5wherein the center portion of one end or face of the blank, as shown anut, is cut away to form a tapered seat portion or shoulder 3 and aninternal tapered wall portion 4. A second longitudinal operation cutsdown the outer wall so as to form an annular clinch-on wall portion orshank 5, a seat 6 being formed all the way around the blank, as shown anut. It will be seen that the clinch-on nut as shown in Fig. 6 may beplaced in a square hole or a hexawith the smaller side thereof curvedconcavely outward, and being preferably cylindric from being formed by arotary end cutter fed along its axis of rotation.

The larger side of the multi-cornered shank 5 r of the nuts of Figs. 7and 8 is curved convexly outward, and corners of the shanks are formedby the outer side edges of the curved faces thereof, the outer cornersbeing as shown, common to each of the curved shank faces.

The attachment article of Figs. 7 and 8 may thus be described, in otherwords, as including a flange with a seat face and a shank extending fromthe seat face, the shank having a plurality of side faces, the sidefaces being curved about different axes, and being preferably cylindric.

To produce such a clinch-on nut as shown in Fig. 6 or as shown in Figs.7 and 8 on a production scale, and at a minimum of cost, I have providedan improved method which may be carried out by a fabricating machine asbest shown in Fig. 1. This machine includes two conveyor members I and 8provided with star wheels 9 for intemiittently advancing the conveyormeans.

Each conveyor unit is provided with a plurality of chucks or clampingmembers it, which are best shown in detail in Figs. 2 and 3. Each chuckis so arranged as to receive the blanks, as shown the nuts 2, which areclamped in position by suitable pivotally mounted clamping arms ii. Atoggle member I! controls clamping or release of the blanks, as shownthe nuts 2, and while no means is shown in Fig. 1 for actuating thetoggle member II, it will be understood that the clamping takes place atthe position l3 and release takes place after the chucks pass thestation it. I

The blanks, preferably flat units, as shown- 9,168,989 performing theoperation shown in Fig. 8 and a tool, the milling cutter 2|, for givingthe clinch over walls or shank a D or c shape with a pinralityofcorners, as best shown in Figs. '1 and 8.

. In the operation of the machine, the centering and fabricating orcutting tools II to II will be continuously rotated by a suitabledriving mechaaim. The back and forth oscillation of the table ll by thecam 22 and the step by step advancement of the conveyors I and I will besynchronized; that is, for example, the conveyor 1 will be moved so thatthe chucks ll will be in the position illustrated in Fig. 1 and thetable ll will be moved to 'the left to the position shown. In thisposition of the table, the centering tools II will select two blankshaving opposite faces, preferably flat units, as shown nuts, from thevertically positioned chutes It and center the same in.the chuck ll.Inasmuch as the chucks are positionedthe same distance apart as thetools ll, ll, 20 and II, it will be seen that during the centeringaction at station II, the blanks, fiat units, or nuts positioned in thechuck at the station It will each be subjected in one face thereof to acounter-boring action to produce the tapered wall portion 4 as shown inFig 5. Likewise the blanks, flat units, or nuts, held in the chuck atshanks I as shown in Fig. 6. At station ll, the shanks l of the twoblanks, fiat units, or nuts positioned in the chuck II will be faced offand formed with a plurality of curved faces and corners by the cylindricend milling cutter-2|, as best shown in F18. '7.

While the blanks, fiat units, or nuts held by the chucks in the conveyor1 are being simultaneously fabricated'at the respective stations, theconveyor I will be advanced one step s? that when the fabricating hasbeen completed on the one side the table II will be shifted so that theblanks,.flat units, or nuts held in the respective chucks on theconveyor -8 will be subjected simultaneously to the respectivefabrications of the several tools.

.It will be thus seen that by using blanks having opposite faces,preferably flat units, as shown standard nuts, and fabricating the sameby means of a machine such as shown in Fig. l, clinch-on nuts may beproduced on a large production scale at an extremely small cost. Thefabrication of the face of the blanks, flat units, or nuts so as to forma clinch-on portion or shank is in every case an axialfabrication'produced by an axial movement of the fabricating tool; thatis, axial with respect to the axis of the thread of the nut, whether ornot. the thread is formed prior or subsequent to the fabrication of theclinch-on portion, or between steps of such fabrication.

In other words, the feed of each rotary cutting or fabricating tool isalong its axis of ro tion into icle bein one face only of the blank, orothers subject to the cutting action of the tools of the machine of Fig.1.

In fabricating a clinch-on nut from a blank having opposite faces,preferably a flat unit, as shown a standard nut, it will be seen that Ihave produced an annular clinch-n wall or shank I formed of the samematerial as the blank, flat unit, or nut body, thus producing a strongwall which may be easily clinched over. Inasmuch as I reduce apreferably square body, it will be seen that the fabrication of theclinch over wall maybeleftinanannular shapeasin Fig.6or

whether the same is given a D or c shape by the operation shown in Fig.7. This makes for much greater strength as compared to the. standard 0clinch-on nut, because in such standard D clinchon nut, there is no seator backing surface adjacent the cut-away D part. Furthermore, thepreferred square baseof the nut makes it much easier to hold in positionwith a suitable clamping tool. As standard nuts have small roundedcorners, it will be seen that the clinch-on nut fabricated from thestandard nut, will present a neat appearance with corners that willnotcatch or tear upholstery or the like which must be pushed past thesame.

It will be understood that the counterboring tools II rotate in acounterclockwise direction, so that when the tool reaches the threads ofthe preferred nut, there will be a clean cut-oif; it will be seen thatif the two operated clockwise that the tendency would be to turn theedge of the nut over instead of cleanly cutting it off. Each of thetools and 2| .may be otherwise described as rabbetlng tools, eachcutting a plurality'of curved or arcuate rabbets in one portion of eachblank, or other articles subject to their action. 1

From this standpoint, the nut shown in Figs. 7 and 8 may be described asconstituting an attachment article including a body having two oppositetransverse end faces, and curved or arcuate rabbets between one of theend faces and the side faces, each rabbet having a transverse seat facelocated between the end faces and a curved preferably cylindric arcuateface at an angle with the seat face and the one end face.

Each of the improved attachment articles hereof may be otherwisedescribed as including a flange or head and a multi-ccmeredshank'extending from the head, the shank having a plurality of externalside faces, each side face comprising a surface of revolution, and beingthus adapted to be machine cut by a rotary cylindric cutting tool.

- in, an arcuate shank extending from one face of the head and about theaperture. and the head having a tapered shoulder formed between theinternal face of the arcuate shank and the threaded aperture.

The embodiment of the improved clinch-on nut and the method of makingthe same illustrated and described herein attains the above statedobjects of the invention, butis by way of example, and the scope of thepresent invention is not limited to the same or to the particulardetails thereof. but is commensurate with any and all novel subjectmatter contained herein. and

which may at any time properly underthe patent laws be set forth inclaims hereof or which may originate herein, the elements of any of theclaims being intended to' include their reasonable equivalents.

I claim: 7

1. As a new product. a standard rectangular nut having one facefabricated to form an arcuate clinch over wall, a portion of said wallbeing cut away to form a C-shape clinch over por- 7 5 tion, a shoulderportion of the nut body adjacent the base of the clinch over wall beingtapered .to center the bolt relative to the thread.

2. As a new product, a standard rectangular nut having one facefabricated to form an arcuate clinch over wall, a portion of said wallbeing cut away to form a C-shape clinch over portion, said wall beingspaced from the edges of said nut to form a shoulder extendingcompletely around the nut for receiving the sheet to which the nut is tobe clinched, and another shoulder portion of the nut body adjacent thebase of the clinch over wall being tapered to center the bolt relativeto the,

thread.

masses and the side surfaces joining each other at the shank corners.

4. An article of manufacture adapted for use as an attachment unit andthe like, including a head and a shank extending from the head, theshank having a c-shape, the external and inter.- nal larger curvedsurfaces of the C and the smaller end surfaces of the c each being asurface of revolution and comprising a side surface of the shank.

FREDERICK N. R088.

